Some Faves:
Buttery Nipple - Shot of butterscotch liquor, float some irish cream - shoot it
Flaming Dr. Pepper - shot of amaretto, float 151 proof rum - light it on fire - dunk it in a chuggable amount of beer, and chug (tastes exactly like a Dr. Pepper)
White Russian - Kahlua + Vodka + cream or 1/2 and 1/2 - on rocks - Be The Dude.
Moscow Mule - Ginger Beer (not ale, BEER) + vodka + lime juice + rocks (put a stick of thyme in it if you feel adventurous, gives a nice bouquet)
Sazerac -
http://www.chowhound.com/recipes/sazerac-cocktail-10330Gin/Vodka Tonic - so simple and easy - gin/vodka + tonic water... optional lime juice, crushed fresh basil, or crushed cucumber
The Godfather - 2 parts scotch (use bourbon in a pinch), 1 part amaretto - on rocks